20210121089 has 2 divisors, whose sum is σ = 20210121090. Its totient is φ = 20210121088.

The previous prime is 20210121079. The next prime is 20210121209. The reversal of 20210121089 is 98012101202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17958144064 + 2251977025 = 134008^2 + 47455^2 .

It is a cyclic number.

It is not a de Polignac number, because 20210121089 - 2¹⁶ = 20210055553 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (20210121079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105060544 + 10105060545.

It is an arithmetic number, because the mean of its divisors is an integer number (10105060545).

Almost surely, 2^20210121089 is an apocalyptic number.

It is an amenable number.

20210121089 is a deficient number, since it is larger than the sum of its proper divisors (1).

20210121089 is an equidigital number, since it uses as much as digits as its factorization.

20210121089 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 576, while the sum is 26.

The spelling of 20210121089 in words is "twenty billion, two hundred ten million, one hundred twenty-one thousand, eighty-nine".